73 Johnson with 65 HP 0 psi on # 3 cylinder please help i wanna go fishing!!!

[JesseNKim]

yesterday we went out on the lake and the first 10 min's she ran like a top we stopped and 3 bass and 2 catfish later decided to move so i fired it up and put put she only does about 10 mph all the way across the river so i said ok theres a problem right?? thats what i thought tell i tried it again and ofcourse again 10 mph all the way across the lake so i said ok theres deffinatly a problem but the 3rd time we ran it back to the dock she ran LIKE A CHAMP !!!! 35 mph all the way back about 10 min's away

now that was yesterday BUTTT when i fire it up on the boat at home with the ears on it it runs LIKE A CHAMP!!

so today i checked compression on all 3 cylinder the top one (#1 cylinder) was 121 psi ok thats good # 2(the middle one) was 120 psi ok thats good BUTTTT # 3 the bottom one had 000's across the board i rechecked my gauge on the # 2 and nope not the gauge hit 120 again on number 2 so whats causing my # 3 to have 0 psi on it and i thought when you drop a cylinder it suppose to run like crappola?? but it doesnt runs great just slow sometimes????

PS: i noticed when i was in water yesterday when i put my finger in front of the bottom carb on # 3 cylinder fuel was sometimes shooting straight out instead of in the cylinder???

WHAT THE HECK IS GOING ON HERE IM STUMPED??

 

[F_R]

Re: 73 Johnson with 65 HP 0 psi on # 3 cylinder please help i wanna go fishing!!!

Assuming it truly is zero compression, something broke inside. Or a blown head gasket. You will have to pull the head and take a look to see what it was. I can't explain why it self-healed temporarily, except if it is a head gasket it may have been firing as water got in/blew out of the cylinder????

 

[JesseNKim]

Re: 73 Johnson with 65 HP 0 psi on # 3 cylinder please help i wanna go fishing!!!

so you think if i pulled the metal plate of the cylinders and take a look to see if rings are broken or scorn on cylinder wall if i dont see that replace the head gasket on the plate i took off and recheck it?

 

[tashasdaddy]

Re: 73 Johnson with 65 HP 0 psi on # 3 cylinder please help i wanna go fishing!!!

thats the first step. then report back. pictures of what you find will help.

 

[JesseNKim]

Re: 73 Johnson with 65 HP 0 psi on # 3 cylinder please help i wanna go fishing!!!

im in process as i type of removing head on the engine to see whats going on in there but have to stop to make son some lunch i will post back in about 30 min's to say whats going on thanks to all who have helped i really appreciate it

 

[Willyclay]

Re: 73 Johnson with 65 HP 0 psi on # 3 cylinder please help i wanna go fishing!!!

The fuel spraying out of the bottom carb makes me think you have one or more bad/broken reed valves for the number 3 cylinder. I'm not an expert, but that would be where I would look after your cylinder inspection. Good luck!

 

[JesseNKim]

Re: 73 Johnson with 65 HP 0 psi on # 3 cylinder please help i wanna go fishing!!!

OKKKKKK my worst fears are coming true to life now i have pulled the head off and all the seals were perfect NOWWW i check the pistons the # 3 cylinder is chewed up a bit and flopping aroind about 1/16 of an inch which tellls me the rings slipped came off and got beat to death on the top of the piston BUT IM NO EXPERT as well as the head itself is chewed a little bit im trying to get pics on here but may not look real good wife broke digital so was taken by camera phone SOOOO where do i go from here do i need a total rebuil or just a piston and a set of rings trust me no expert??

ok i have attached 2 pictures one with the chewed up piston and other with the chewed up head cover

 

[JesseNKim]

Re: 73 Johnson with 65 HP 0 psi on # 3 cylinder please help i wanna go fishing!!!

ok head cover size was too large but you get the idea

WHERE DO I GO FROM HERE??

 

[jay_merrill]

Re: 73 Johnson with 65 HP 0 psi on # 3 cylinder please help i wanna go fishing!!!

OK - complete re-edit here because I just saw your pic and explanation. I'm thinking that you had a fuel delivery problem in the lower cylinder, causing a lack of lubrication and eventual ring failure. The pits in the piston crown look to me like they were caused by bits of the ring getting up into the cylinder bore. That said, you may have some damage to the inside of the head, along with the piston and cylinder wall damage.

Suffice it to say that you will not be going fishing with this motor today. Where you go from here is to do an overhaul of the powerhead or find another motor. Sorry, but that's just the reality of the situation.

 

[JesseNKim]

Re: 73 Johnson with 65 HP 0 psi on # 3 cylinder please help i wanna go fishing!!!

can you explain a little about the overhaul i mean im pretty sure with the book i have on the motor i can put in new pistons rings and connecting rods and have cylinder honed myself but is that all thats needed??

ofcourse while im doing this i will replace the reeds and rebuild carbs to make sure no more deliver problems lol

 

[tashasdaddy]

Re: 73 Johnson with 65 HP 0 psi on # 3 cylinder please help i wanna go fishing!!!

you really won't know till you get inside. open it up. start with the exhaust covers and you can see more. what do the cylinder wall look like? you are in for a rebuild, may as well do it complete and have a new powerhead. or price the items necessary, and make a decision on whether to rebuild, or replace the power head, or the complete motor. remember you are putting money into a 35 year old motor. value $500-1,000.

 

[JesseNKim]

Re: 73 Johnson with 65 HP 0 psi on # 3 cylinder please help i wanna go fishing!!!

think i may just sell it as a running parts motor because just the pistons rings and connecting rods is 432$ and if you buy a new powerhead for it its over 1000 just for that i really appreciate everyones help but i think its a goner for me anywaysz thanks everyone!!

 

[tashasdaddy]

Re: 73 Johnson with 65 HP 0 psi on # 3 cylinder please help i wanna go fishing!!!

that may very possibly be your best bet, then look for a mid 80's or newer.

 

[jay_merrill]

Re: 73 Johnson with 65 HP 0 psi on # 3 cylinder please help i wanna go fishing!!!

I agree with TD that you have probably made a good decision regarding this powerhead. If, however, the rest of the motor is still in good shape (particularly the gearcase, gears. etc.) you might want to look around for a powerhead. You can sometimes find them on EBay, or other places, when someone is parting out a motor that had some sort of other major failure. You do not necessarily have to find a 1973 65hp powerhead, either. There may be a number of them of different years and/or hp ratings that will bolt directly on your engine. Just be sure to do the homework before plunking your dollars down on something that may or may not fit.

 

[JesseNKim]

Re: 73 Johnson with 65 HP 0 psi on # 3 cylinder please help i wanna go fishing!!!

i just found a complete running powerhead on ebay for a 65 hp that is same year and good compression ratings for 285 with shipping BUT my quistion is this something i can swap myself with no outboard experince other than water pumps i mean im very good with my hands and i have a repair manual?

also is that a good prise he says read 116 on number 1
126 on number 2
118 on number 3?

i will rebuild my carbs and starter before rebuilding this but is it worth the 280 do you guys think and can i do it myself what is involved with changing out a powerhead?

 

[iwombat]

Re: 73 Johnson with 65 HP 0 psi on # 3 cylinder please help i wanna go fishing!!!

It's a good price, and the compression readings are all within 10%.

My take - if you're confident about tackling a carb rebuild, then a powerhead swap is probably within your grasp too. Not much to it as long as things come apart ok.

A digital camera will be your best friend. Take lots of pictures at various stages of undress. Put all parts in plastic bins, or sturdy boxes and neatly organized.

 

[jay_merrill]

Re: 73 Johnson with 65 HP 0 psi on # 3 cylinder please help i wanna go fishing!!!

I agree that if you are reasonably mechanically inclined, have the tools needed and a decent manual, you should be able to do this. If you don't have an OMC service manual for the motor, PM me with an email address and I'll send the powerhead section of the manual to you. I don't recommend that you rely on the aftermarket manuals to do this job because most of them aren't worth much IMO.

 

[tashasdaddy]

Re: 73 Johnson with 65 HP 0 psi on # 3 cylinder please help i wanna go fishing!!!

agree^^^^^ good price. i just parted out an 18 hp, because some one gnarled the threads on the crank shaft.

 

[Lakester]

Re: 73 Johnson with 65 HP 0 psi on # 3 cylinder please help i wanna go fishing!!!

Put all parts in plastic bins, or sturdy boxes and neatly organized.

hello,

and lable them. make notes, too.

can u describe the condition of the bore in hole #3? scoring, marring, deep scratches? with piston at TDC can u see any ring damaged areas?

interesting post. sorry to hear it happened. wonder what caused the potential fuel delivery to hole #3 that was tied the its carb spitting?

regards
lakester

 

[JesseNKim]

Re: 73 Johnson with 65 HP 0 psi on # 3 cylinder please help i wanna go fishing!!!

sorry i didnt reply sooner had to go to work GRRRR but anyways took a REAL good look when ileft for work and noticed some good scoring where the motors been ran by me lol after this had happend but no more than 45 min's of running im guessing after it happned what it looks like to me with a powerhead swap is basically like doing a motor swap in a car just unhook it from the lower unit(the transmission of the car) and pull it off and slap the new one on it right? and my email is JAYISMYNIKNAME@AOL.COM please send me ANY INFO on the powerhead manuals part number anything i can use so i can MAKE SURE to get the right one lol only want to deal with this once lol

AGAIN THANKS AND MANY MORE TO ALL WHO REPLIED AND YES ITS SAD I LOVE THIS OLD 73 BOAT BUTTTTTTTTTTT ieven though i just rebuilt the carpeted area installed a cd player and 2 new speaker and new depth finder and steering unit and steering wheel and all 4 seats im pretty sure im NOT GONNA BUY A NEW MOTOR FOR IT i will buy a used boat before i did that and take all my parts out of it and junk the rest or sell the shell which is in great ciondition THEY DONT MAKE THEM LIKE THEY USED TO YOU KNOW WHAT I MEAN!!!!